I actually brought this scenario up to a friend of mine as well. I too thought for a minute that since the entire city now knows that Batman sacrificed himself for the city that they would put two and two together that he was Wayne since he died as well.

However after much discussion, Wayne could have easily died during Bane's invasion especially since he seemed to target the 1% which Bruce was a part of. Even though Wayne was publicized to have lost everything, he still had more than many. Many of the wealthy died or nearly died during those almost 3 months during Bane's rise to power and execution of the next era of western civilization.

So in the end the city would have simply brushed Wayne's death aside as another victim who died by Bane's hand or even his own after he had lost everything.